A feeding well takes an important role in a solid-filling coal mining system, and is the throat for transport of the solid filling material. Hence, the serious wall abrasion of the feeding well has direct impact on the progress of fill mining. The surface deformation of the feeding well is mainly the result of abrasion by solid materials. At present, devices for detecting well wall deformation mainly include panoramic well wall scanning devices and other well wall surface deformation sensors. On one hand, these devices are expansive; on the other hand, they cannot measure well wall abrasion and deformation intuitively. Therefore, it is especially important to develop a device and a method for detecting wall abrasion of a solid-filling feeding well that are convenient to install and have low cost.